U.S. patent application number 10/311598 was filed with the patent office on 2003-10-09 for side by side twin spreader and method.
Invention is credited to Lindstrom, Lennart.
Application Number | 20030189348 10/311598 |
Document ID | / |
Family ID | 20280206 |
Filed Date | 2003-10-09 |
United States Patent
Application |
20030189348 |
Kind Code |
A1 |
Lindstrom, Lennart |
October 9, 2003 |
Side by side twin spreader and method
Abstract
A spreader has an elongate main-frame (1) arranged to be
suspended in cables from a crane, and twist locks are arranged in
the ends of the spreader for simultaneously connecting to two
containers (4, 5) arranged in side by side relation. Two pairs of
twist locks (3) are arranged in each end of the spreader, the twist
locks of each pair having a fixed lateral distance (a) and the
pairs of twist locks being laterally movable and controlled for
adjustment of a lateral distance (b) between the pairs of twist
locks. A method for processing two containers in side by side
relation in a single lowering/lifting step, and for adjustment of a
lateral distance and/or lateral, relative angle between the two
containers during transfer and lowering to release the containers
in side by side relation.
Inventors: |
Lindstrom, Lennart;
(Vallingby, SE) |
Correspondence
Address: |
YOUNG & THOMPSON
745 SOUTH 23RD STREET 2ND FLOOR
ARLINGTON
VA
22202
|
Family ID: |
20280206 |
Appl. No.: |
10/311598 |
Filed: |
December 18, 2002 |
PCT Filed: |
June 21, 2001 |
PCT NO: |
PCT/SE01/01439 |
Current U.S.
Class: |
294/81.53 |
Current CPC
Class: |
B66C 1/663 20130101;
B66C 1/104 20130101 |
Class at
Publication: |
294/81.53 |
International
Class: |
B66C 001/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 22, 2000 |
SE |
002351-5 |
Claims
1. A spreader for simultaneously processing by lifting,
transferring and lowering of two containers in side by side
relation, the spreader comprising an elongate main frame (1)
arranged to be suspended in cables from a crane; two sub-frames
(6,7), suspended from the main frame and running in the
longitudinal direction thereof; a pair of twist locks (3) arranged
in each end of the sub-frames for connection to the upper corners
of said two containers, the twist locks of each pair of twist locks
being spaced by a fixed lateral distance (a) transversely to the
longitudinal dimension of the spreader, and each pair of twist
locks being laterally movable in the transverse direction for
adjustment of a lateral distance (b) between the pairs of twist
locks in each end of the spreader, characterized by drive means
(20) associated with the sub-frames and controllable for separate
adjustment of the lateral distance (b) between the pairs of twist
locks in each end of the spreader, and wherein each sub-frame (6,7)
is suspended from the main-frame (1) by means of rods (10) arranged
in pairs and running in parallel from each end of the main-frame,
and the rods are pivotally connected to the main-frame and the
sub-frame, respectively, for a substantially planar, lateral
displacement of the sub-frames in order to adjust the lateral
distance and/or the relative angle between the sub-frames, and thus
between the containers connected to the spreader.
2. The spreader of claim 1, wherein the main-frame (1) comprises
two end beams (13) transversely connected to the ends of at least
one longitudinal beam (12), each end beam being suspended from a
trolley (14) that is displaceable on the end beam in transverse
directions of the spreader, and each sub-frame is suspended from
the end beams to be individually displaceable in said transverse
directions.
3. The spreader of claim 2, wherein each sub-frame (6,7) is
associated with a pair of drive means (20) for transverse
displacement of the sub-frame, the drive means (20) being arranged
to operate between the end beams (13) and the sub-frames (6,7).
4. The spreader of claim 3, wherein the end beam has an upper guide
means (17) on which the trolley (14) is controlled for sliding
displacement in said transverse directions, and a lower guide means
(19) on which the sub-frames are controlled for sliding
displacement in side transverse directions.
5. The spreader of claim 4, wherein the trolley (14) is attached to
a carriage (16), and a drive means (15) controls the carriage to be
guided by the upper guide means (17) in a sliding displacement of
the trolley in said transverse directions.
6. The spreader of claim 4, wherein the sub-frame (6,7) is
suspended by rods (10) from a carriage (18), and a drive means (20)
controls the carriage to be guided by the lower guide means (19) in
a sliding displacement of the sub-frame in said transverse
directions.
7. The spreader of any previous claim, wherein said rods (10) are
formed as cables or chains (10).
8. The spreader of claims 1 to 7, wherein said rods (10) are rigid
struts of adjustable length.
9. The spreader of any previous claim, wherein the sub-frames (6,7)
are interconnected by additional drive means (8) directly operating
between the sub-frames.
10. Method for simultaneously processing by lifting, transferring
and lowering of two containers in side by side relation by means of
a spreader according to claim 1, wherein the spreader is lowered to
connect with the two containers and then to lift the containers in
side by relation in a single lowering/lifting step; the spreader is
controlled to adjust a lateral distance (b) and/or to adjust a
lateral relative angle between the containers during transfer, and
the spreader is lowered to release the containers in side by side
relation in a single lowering step.
11. The method of claim 10, wherein a common load center for the
containers is adjusted by lateral displacement of one or both
sub-frames (6,7) relative to the trolley (14) in a transverse
direction of the spreader.
12. The method of claim 10, wherein one or both sub-frames (6,7)
and the trolley (14) are controlled for lateral displacement
relative to a load center of the spreader.
13. The method of any previous claim, wherein the sub-frames (6,7)
are controlled for a non-parallel, lateral displacement in a common
plane.
Description
TECHNICAL FIELD
[0001] The present invention relates to spreaders as generally
defined in the preamble of claim 1. More closely, the invention
relates to spreaders for lifting two containers simultaneously,
side by side in a lateral plane. In the preferred embodiment, the
spreader is designed for adjustment of the relative angle and
lateral distance between the containers under the lifting motion.
The invention also relates to a method for lifting, moving and
lowering of two containers in side by side relation.
[0002] In the field of container transport, efforts are
continuously made in order to reduce port stops and the time needed
for loading/unloading of ships, railroad and road units.
Significantly at ship terminals, where large quantities of goods
are handled by containers, development is heading towards larger
units and towards more rational methods for loading and
administration of the large goods quantities. Beside an increasing
number of containers reaching 40' or more in length, the recent
development is also directed towards the simultaneous processing of
two containers in lifts from ship to shore--or the reverse.
PRIOR ART
[0003] In this technical field spreaders are known with a capacity
for lifting a single 40' container, or optionally two 20'
containers in a single operation as in WO97/39973 (Stinis, N L),
e.g. In the last case the two 20' containers are axially oriented,
the end wall of one container facing an end wall of the other. This
spreader is also known to have a capacity for adjustment of the
spacing between the two 20' containers longitudinally under
lift.
[0004] A spreader for lifting two containers in side by side
relation is known from SE-A-80034085 (A B Hagglunds & Soner, S
E). In this arrangement, two sub-spreaders are pivotally supported
by a superstructure in side by side relation for engagement with
two containers to be lifted and moved. The sub-spreaders are
adjustable lengthwise, but are not able to perform a lateral
adjustment of the spacing between the two containers in a lateral
plane, or a non-parallel displacement of the two containers.
SUMMARY OF THE INVENTION
[0005] In order to meet a need and desire for even more rational
processing and reduction of time required for loading/unloading of
containers, the present invention aims to provide a solution
wherein a spreader is designed for engaging, lifting, moving and
lowering two 40-48 feet containers in side by side relation, with a
capacity to adjust the lateral spacing between the containers in a
parallel or in a non-parallel displacement, as desired.
[0006] This object is met in a spreader as defined by the
characterizing features of claim 1, and by a method as advised in
claim 10. Advantageous embodiments are defined in the
sub-claims.
[0007] Briefly, the present invention suggests a spreader having a
main frame or main beam supported by cables from a crane. Locking
means (twist locks) are arranged in the ends of the spreader for
engagement with correspondingly formed corner boxes in the upper
corners of a container. More specifically, two pairs of twist locks
are arranged in each opposite end of the spreader such that each
pair of twist locks is aligned transversely to a longitudinal
extension of the spreader. In the transverse direction, each pair
is supported with a substantially fixed lateral distance between
individual twist locks within each pair, whereas at least one pair
of twist locks in each end of the spreader is laterally movable in
the transverse direction for adjustment of a lateral spacing
between the two pair of twist locks in the end of the spreader.
[0008] In a preferred embodiment, the suggested spreader has twist
locks arranged in pairs in opposite ends of two sub-frames
suspended from the main frame. At least one of the sub-frames is
driven and controlled in the transverse direction for separate or
contemporaneous adjustment of the lateral distance and/or relative
angle in a lateral plane between the two sub-frames, as
desired.
[0009] By the invention there is also provided a method for
simultaneously processing two individual containers in side by side
relation by means of a single spreader and crane. In the method,
the spreader is lowered for connecting to the two containers
arranged side by side, mechanically connecting the eight twist
locks of the spreader in a single lowering step. The containers are
then lifted and moved side by side to be simultaneously lowered,
and optionally, simultaneously disconnected from the spreader. In
the lowering and/or transfer motions, the pair of twist locks in
both ends of the spreader are optionally driven and controlled
transversely to the longitudinal direction of the spreader for
positioning the containers in a desired inter-spaced relation, or
at a desired relative angular position.
DRAWINGS
[0010] Exemplary embodiments of the invention are further described
below, reference being made to the accompanying, schematic drawings
wherein
[0011] FIG. 1 is an end view showing the fundamental operation of a
spreader according to the invention;
[0012] FIG. 2 is an end view showing a first embodiment of a
spreader according to FIG. 1;
[0013] FIG. 3 is a top view showing a pair of sub-frames in the
spreader of FIG. 2;
[0014] FIG. 4 is an end view showing a second embodiment of the
spreader, the sub-frames being supported by rods from a main
frame;
[0015] FIG. 5 is an end view showing a preferred embodiment of the
spreader;
[0016] FIG. 6 is a top view of the spreader in FIG. 5;
[0017] FIGS. 7a and 7b are end views showing the sub-frames in
different lateral positions, and
[0018] FIG. 8a-c are end views showing a further embodiment of the
spreader, the sub-frames being displaced to different lateral
positions.
DETAILED DESCRIPTION OF EMBODIMENTS
[0019] The principals of the spreader according to this invention
will now be described with reference to FIG. 1.
[0020] An elongate main frame 1 is arranged and supported by cables
2 from a crane (not shown). In each end of the main frame, twist
locks 3 are arranged for engagement with correspondingly formed
corner boxes in the upper corners of a container. Each opposite end
of the spreader carries two pairs of twist locks 3 arranged
transversely relative to the longitudinal dimension of the main
frame 1. The twist locks 3 of each pair of twist locks are secured
at a substantially fixed lateral width a in the transverse
direction. At least one pair of twist locks in each end of the main
frame is laterally movable relative to the other pair, at least in
said transverse direction for adjustment of a relative lateral
distance b such that the spreader is connectable to the two
containers 4,5 in side by side relation.
[0021] A first example of a spreader according to the invention is
illustrated in FIG. 2. In the spreader of FIG. 2, twist locks 3 are
arranged in pairs in the opposite ends of two sub-frames 6 and 7,
respectively, suspended from the main frame 1. At least one of the
sub-frames 6,7 is driven and controlled in the transverse direction
for adjustment of the lateral width b in one or both ends of the
spreader, separately or simultaneously as desired. The operation
provides an optional adjustment of the relative angular position
between the sub-frames 6,7, and between the containers that are
gripped by the twist locks.
[0022] As illustrated in FIG. 3, the sub-frames 6,7 may be
interconnected such that the drive means for adjustment of lateral
distance and relative angle are arranged to operate directly
between the sub-frames. More precisely, the sub-frames 6,7 are
interconnected on each side of a longitudinal center of the main
frame by means of arms 8,9, respectively, the arms being adjustable
relative to the lengths thereof. The arms may be realized as
double-acting cylinders 8,9. Each end of the arms 8,9 is pivotally
attached to a sub-frame, and separately controlled for adjustment
of lateral distance and relative angle between the sub-frames 6,7
and also between the containers 4,5 connected to the twist locks 3.
The sub-frames 6,7 may further be telescopic and adjustable
relative to the lengths thereof.
[0023] FIG. 4 shows a second example of the spreader wherein the
sub-frames 6,7 are pivotally suspended by rods 10 in each end of
the main frame 1. In this embodiment each end of a sub-frame is
suspended by rigid rods of adjustable length forming a
parallelepiped, by which will be ensured a substantially lateral or
horizontal orientation of the sub-frame, and of a container carried
by the sub-frame, upon adjustment of the lateral distance b between
sub-frames 6,7.
[0024] As illustrated in FIG. 4, the sub-frames 6,7 may be
suspended from a common, transverse guide means 11 that is driven
and controlled for a lateral displacement of a load center relative
to the wires 2.
[0025] FIG. 5 illustrates a preferred embodiment of the side by
side twin spreader according to the invention. A main frame 1
comprises a pair of longitudinal beams 12, the ends of which (shown
in broken lines in FIG. 5) are connected to transverse end beams
13, respectively (only one visible in FIG. 5). The main frame 1 has
a generally H-formed plan view as will be apparent from FIG. 6.
[0026] The end beams 13 are suspended from a trolley 14, hanging in
cables from a crane (not shown). The trolley 14 is slidable along
the end beam 3, transverse to the longitudinal direction of the
spreader 1. The trolley 14 is associated with a driving means 15
that operates between the end beam 13 and the trolley for
displacement of the trolley in compensation for a displaced load
center due to an uneven load on the sub-frames 6,7. The driving
means may be realized as a hydraulic cylinder 15 that moves a
carriage 16. The carriage 16 is guided for sliding motion on the
end beam 13 by gripping below a flange or slide guide 17, formed
near a top portion of the end beam 13.
[0027] The sub-frames 6,7 are suspended in rods 10, realized as
chains 10, from the end beams 13. The cables 10 run in pairs from
each end of the sub-frame, and in parallel relation from the
sub-frame to a carriage 18 that is guided for sliding motion on the
end beam 13. The carriage 18 may be formed for engagement with a
flange or slide guide 19, formed near a bottom portion of the end
beam 13. Driving means 20 is arranged to operate between the end
beam and the carriage 18 for a lateral displacement of the
sub-frame in an axial direction of the end beam 13. The driving
means preferably is a hydraulic cylinder 20.
[0028] FIG. 7a is an end view showing the sub-frames 6,7 brought
together in a closely related position, and FIG. 7b shows the
sub-frames in a lateral, symmetrically expanded relation wherein
all driving means 20 are equally activated and the sub-frames are
running in parallel with a distance b there between. It should be
noted that the lateral displacement of the sub-frames is
controllable through the driving means 20 for bringing the
sub-frames to any desired lateral position, and also for changing
the relative angular position such that the sub-frames may be
displaced from the parallel relation.
[0029] FIGS. 8a-c are end views illustrating an alternative
embodiment wherein a further cylinder 8 is arranged to operate
directly between the sub-frames 6,7. The drawings show the lateral
displacement of the sub-frames while maintaining a substantially
planar relation for connecting to the corner boxes of two
containers in side by side relation.
[0030] Without being illustrated in the drawings or further
described herein it should be mentioned that in all embodiments the
twist locks 3 may be arranged on the sub-frames for a limited
freedom of motion in all radial directions in a plane that is
parallel to the sub-frame. The twist locks may also be arranged for
a limited freedom of motion relative to the sub-frame in opposite
directions transversely to a plane that is parallel to the
sub-frame. In order to compensate for a non-planar condition of the
containers when lowering the spreader for connection with the
corner boxes of containers in side by side relation, or when
lowering the containers to rest in a new position on non-planar or
leveled grounds, the twist locks may advantageously be axially
movable in vertical direction. The vertical movement of the twist
locks is preferably damped in at least one vertical direction by
means of resilient or elastic elements incorporated in a structure
for holding the twist locks in the sub-frame.
[0031] The invention provides a method for simultaneously
processing two containers in side by side relation with a spreader.
In the method, the spreader is lowered for connecting the two
containers in one single lowering step by controlling four pairs of
twist locks from a main frame. The two containers are lifted and
transferred from a first position to be lowered and disconnected
side by side in a new position. During transfer and/or lowering of
the containers, the twist locks in the ends of the spreader are
driven and controlled in pairs for adjustment of a lateral distance
b between the containers, and/or for adjustment of the relative
angle between the containers in a lateral plane.
[0032] The spreader, and the method of the invention, is
significantly advantageous for lifting two containers in side by
side relation from load cells in a ship. In the lowering step, cell
guides of the load cells direct the sub-frames and the drive means
for adjusting the lateral distance b may be released. During lift
and transfer of the two containers, the lateral distance and
relative angle between sub-frames and thus between the containers
may be manipulated before lowering the containers to the new
position, such as a quay, load vehicle or lorry. The separately
controlled pairs of twist locks in the ends of the spreader allow
for an accurate positioning of the containers also when the ground
surfaces or load platforms are of different heights and not in
parallel. The same advantages apply also when the process is
reversed.
[0033] The invention provides a significant improvement when
applied for twin lifts of containers having lengths of 40' or more.
The principles of the invention may naturally be applied for
containers of other and shorter lengths as well.
[0034] The transversal movements that are utilized in the new
spreader may advantageously be produced by electric motors,
cylinders driven by air or fluid, gear drives, cables or other
driving means and motion transfer means as are known per se in this
technical field. Motion control may comprise limit switches,
optical detectors and control electronics with software. Load
detectors may be incorporated in order to detect uneven load on the
spreader.
[0035] The motion that is generated for adjusting the lateral
distance between the sub-frames may be controlled in respect of a
detected load distribution for displacement of one or both
sub-frames relative to the end beam, in order to adapt the spreader
to the common load center of the two containers. Thus, the spreader
provides alternative mechanisms for distribution of the load:
through adjustment of the trolley relative to the load center of
the containers, and/or through moving the load center by adjustment
of one or both sub-frames relative to the trolley.
* * * * *